There was a thread about funnel cakes and how to make them behave but I can't find it right now--we've been using with good success a Presto Kitchen Kettle which is just a little electric cauldron.

It's $25, you can get it at Wal-Mart, if you turn it all the way up it is capable of frying nicely, it is the perfect size and shape, smooth bottom and non-stick. Flip with tongs in each hand. On a busy Saturday we have two of them in production making $4 funnel cakes continuously.

Most municipalities require equipment used to serve food in commercial applications to be NSF rated. I'm in the Chicago area and know the health department requires mfg cut sheets on each piece of equipment used to prepare food.